Thermal-controlled shutter.



E. CAHILL.

THERMAL CONTROLLED SHUTTER.

APPLICATION FILED SEPT. 8. 1915.

1+-,;203;47. Patented Nov. 7, 1916.

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E. CAHILL.

THERMAL CONTROLLED SHUTTER.

APPLICATION FILED S EPT. 8, I-9I5.

PatentedNov. 7, 1916.

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THERMAL-GONTROLLED SHUTTER.

1 Specification of Letters Patent.

Patented Nov. 7, 1.916.

Application filed September 8, 1915 Serial No. 49,599.

To all whom it may concern Be it known that I, EDWARD CAI-IILL, a citizen of the United States, residing at New York, in the county and State of New York, have invented certain new and useful Improvements in Thermal-Controlled Shutters, of which the following is a full, clear, and exact specification.

This invention relates to thermal-coir trolled shutters or doors for automatically closing passage-ways or windows in case "of fire in order to prevent an extensive conflagration.

It is the aim of this invention to provide a closure of this kind which will be more reliable-in operation but which will not be apt to be released accidentally, such accidental release in prior devices having caused the stripping of gears and sometimes even the loss of life.

Another object is to provide improved cushioning means for checking the descent of the shutter as it nears its fully closed position.

Other objects'will appearas the description proceeds. V

The invention will be first hereinafter described in connection with the accompanying drawings, which constitute a part ofthis specification, and then more specifically defined in the claims'at the end of the description.

In the accompanying drawings, wherein similar reference characters are used to designate corresponding parts throughout the several views: Figure leis a front elevation of a shutter constructed substantially in accordance with the present invention, said shutter being illustrated in its closed or lowered position... Fig. 2 is'a longitudinal vertical section through theshutter and the means for supporting the same. Fig. 3is a broken horizontal section through the hollow shaft on which the shutter is rolled. Fig. 4f an enlarged transverse section through the left hand end portion of the shaft, showing the locking pawl in active position, as when the shutter is held in its raised position and the fusible link and chains connected thereto are fastened in the position indicated in dotted lines in Fig. 1. Fig. 5 is a similar view showing the pawl out of locking position, as when the fusible link has been separated by excessive heat andthe'jshutter'has been dropped. Fig. 6 s a d ai e iew the tamer gears t is adapted to move vertically in guiding grooves 2 at the sides of the passage-way 3. it the top ofthe passageway the shutter is attached to collars ii: fast on 'a hollow shaft 5 which is inclosed in a casing 6. The shaft 5 is hollow. and has its left hand end journaled around a hollow lug 7 which is part of a supporting bracket 8. Journaled within the lug 7 and, preferably running within ball-bearings 9, is a notched wheel 10, the shank 11 of which extends entirely through the h1g7. A coiled spring 12 is housed within the left hand section of the shaft 5 and has one of its ends attachedto the inner end of the shank 11 of the notched wheel 10, the other end of the spring being fastened to a pin 13 fitted transversely to the shaft.

The right hand end of the shaft 5 is fastened to a collar let journaled around a stud 15 rigidly fastened to right hand end plate 16 of the casing 6. The stud 15 extends inward beyond thecollar 14c and is attached to one end of a, coiled spring 17 which is housed in the right hand end section of the shaft 5. The other end of the spring 17 is fastened to a transverse pin 18 fixed to the shaft. The collar 14 preferably has ballbearings 19 between it and the stud 15, and has a gear wheel 20 rigidly mounted thereon beyond the end of the shaft 5. A train of gears 21 communicate rotary motion from the collar 1e, andshaft 5 which is rigidly fastened to thesame, to an auxiliary shaft 22 also carrying a sprocket wheel 23. Another sprocket wheel is journaled nearthe bottom of the passageway and is provided with an operating crank 24. A sprocket chain 25 passes over the sprocket wheel 23 and the one operated by the crank 24, so that by turning said crank the shaft 5 may be rotated for raising or rolling up the shut ter 1.

Pivotallymounted on the left hand end wall 26 of the casing 6 is a pawl 27 having two teeth or proiections 28 and 29 at opposite ends thereof. The pawl is pivoted at 30 near the end bearing the tooth 28, which is the lower end of the pawl when the same is n locklng position, as'shown in Fig. 4.

IV hen in this position, the teeth 28 and 29 extend into adjacent notches 31 in the wheel 10 and the pawl is arranged in an inclined position so that when released it will automatically swing down to the unlocked position illustrated in Fig. 5. The pawl is arranged in looking position, Fig. 1, when the shutter has been rolled up on the shaft 5, and said pawl is held in this position by a chain or other flexible connection 32 which is passed over bearing pulleys 33 above the shaft and within the casing 6, and down through the bottom portion of the casing and along'thc front thereof where it is secured by a fusible link 31, Fig. 1. The fusible link may be fastened directly to the bot tom of the casing, or another section of chain 35 may be connected to said link and have its other end made fast to the right hand end of the casing, see Fig. 1.

Vhen the shutter is installed, the tension of the spring 17 is, according to the weight of the shutter, made such as to prevent its violent descent when the shutter is liberated from the tension of the spring 12. The tension of the spring 17 also permits the shut ter to be evenly rolled up by means of the crank 24 acting through the sprocket chain 25 and train of gears 21. When the pawl 27 is engaged with the notched wheel 10 for supporting the shutter in raised or rolled up position, the spring 12 is tensioned to retain or counterbalance the shutter. Now, when the pawl is released from the notched wheel 10, which will occur whenever the temperature rises sufficiently to fuse the link 3%, as in case of fire, the tension of the spring 12 will be relieved and the counterbalance being thus destroyed, the shutter will fall from its own weight. As the shutter falls, the tension on the spring 17 is increased so as to cushion to a certain ex tent the descent of the shutter.

To further cushion the fall of the shutter I provide a chain 36 fastened at one end to the lower edge of the shutter and at the other end to a block 37 arranged half way up the passageway and cushioned by a spring 38. The block 37 and spring 38 are both mounted upon a vertical rod 39 which serves as a guide for said block. It will be readily understood that as the lower edge of the shutter nears the bottom in its fall, the chain 38 will become taut and pull downward upon the block 37 against the force of the cushioning spring 38.

As illustrated in Fig. 7, instead of coiled springs arranged within a hollow shaft, clock springs 10 may be placed within the collars 41 to which the shutter is attached, said collars being loose on the shaft 42, and each of the springs 10 being fastened at one end. to the shaft and at the other end to the collar. This construction is especially designed for small shutters.

As shown in Fig. 8, the locking pawl may be made in the form of a bell crank lever having a relatively long extending arm -13 from the pivot 14: to the connection with the chain 45 which corresponds to the chain 32 already described, said arm 13 giving additional leverage for supporting the pawl in locking position. Referring again to Fig. 4, and the sameis true in Fig. 8, the tooth 29 at the free end of the pawl 27 serves to lock the wheel 10 by engaging one of the notches 31 in its periphery. The other tooth 28 extends into another notch 31 in the wheel 10 and when the pawl is released is struck by the wall of said notch, thereby throwing the pawl outward with the tooth 29 entirely free from the notch which it had engaged. Both of the teeth 28 and 29 are pitched so as to engage only one of the walls of each notch.

It will thus be seen that I have provided a thermal controlled shutter or door with a loose shaft which facilitates my desired object, for upon release of spring the shaft 5, which is journaled around the hollow lug 7, is driven reverse to wheel 10 and positively releases the pawl. It will also be noticed that gravity, without the aid of the spring, will also release the pawl when link is fused.

It will further be observed that I have provided eight notches 31 in wheel 10, which aid in securing a very desirable result in the regulating or counterbalancing of the springs, so that the spring counterbalance can be varied by one-eighth of a turn either way in order to obtain a perfect counterbalance for the rolling shutter.

While I have shown some of the train of gears 21 arranged outside the end plate or bracket 16, in Figs. 1 and 6, it will be understood that all of these gears may be inclosed in the casing 6, or if desired parts shown inclosed may be exposed without departing from my invention,

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. The combination, with a hollow shaft adapted to carry a rolling shutter, of a notched wheel having a shank extending into one end of the shaft, a supporting bracket having a hollow stud extending into the shaft for journaling the same and through which the shank of the notched wheel extends, a counterbalancing spring attached at one end to said shank and at the other end to the shaft, a pawl'adapted to be secured in locking position engaging a notch in said wheel, and thermal control means for releasing said pawl. 7

2. The combination, with a hollow shaft adapted to carry a rolling shutter, of a notched wheel having an integral shank extending into one end of the shaft, a supporting bracket having a hollow stud eX- shaft, a pawl adapted to be secured in looktending into one shaft for journaling the ing position engaging a notch in the Wheel, same and through Which the shank of the and thermal control means for releasing 1/ notched Wheel extends, said shank terinisaid 'pawl.

55 nating at its inner end near said stud, a In testimony whereof I have signed my counterbalancing spring attached at one end name to this specification.

' to said shank and at the other end to the EDVARD CAHILL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D C. 

